1. Field of the Invention
The present invention relates to medical cannula packaging, and more particularly, to packaging for dispensing and storing a medical cannula.
2. Description of the Related Art
Medication delivery pens are used for self-injection of precisely measured doses of medication. Pens are widely used, for example, by diabetics to self-inject insulin. A typical medication delivery pen includes a cartridge which contains a volume of liquid medication sufficient for several doses. Using a disposable pen needle attached to the pen device, the dose is injected into a tissue area, such as the intramuscular tissue layer, the subcutaneous tissue layer, or the intradermal tissue layer.
Pen injection devices, such as the exemplary pen injector 50 shown in FIGS. 1 and 2, typically comprise a dose knob/button 24, an outer sleeve 13, and a cap 21. The dose knob/button 24 allows a user to set the dosage of medication to be injected. The outer sleeve 13 is gripped by the user when injecting medication. The cap 21 is employed by the user to securely hold the pen injector 50 in a shirt pocket, purse, or other suitable location.
FIG. 2 is an exploded view of the exemplary drug delivery pen 50 shown in FIG. 1. The dose knob/button 24 has a dual purpose and is used to both set the dosage of the medication to be injected and to inject the dosed medicament via a lead screw 7 and stopper 15 from a medicament cartridge 12, which is attached to the drug delivery pen through a lower housing 17. The medicament cartridge 12 is typically a glass tube sealed at one end with a septum 16 and at the other end with the stopper 15. In standard drug delivery pens, the dosing and delivery mechanisms are all found within the outer sleeve 13. Those mechanisms are not described in greater detail herein because they are understood by one of ordinary skill in the art.
A pen needle assembly 10 includes a hub 20, a hollow patient needle 11 extending from a patient end of the pen needle assembly, and a septum-penetrating needle cannula 18 disposed within the hub 20 on a non-patient side thereof. The septum-penetrating needle cannula 18 is in fluid communication with the patient needle 11. The hub 20 is preferably threaded onto the lower housing 17, although other attachment means can be used such as attaching directly to the medicament cartridge 12. In attaching the hub 20 to the lower housing 17 or medicament cartridge 12, the septum-penetrating cannula 18 pierces the septum 16, but the septum 16 does not move with respect to the medicament cartridge 12. The stopper 15, however, is axially displaceable within the medicament cartridge 12 while maintaining a fluid-tight seal. The distal movement of the plunger or stopper 15 within the medicament cartridge 12 (due to advancement of the lead screw 7) causes medication to be forced into the patient needle 11 of the hub 20.
To protect a user, or anyone who handles the pen injector 50, pen needle assemblies are usually individually packaged inside a plastic cover with a peelable label covering the opening in the cover to provide a sterility barrier. For example, a rigid outer shield 29 attaches to and covers the hub 20. The outer shield 29 can also be used as a handle or grip to screw the hub 20 onto or off of the pen injector 50. Typically, a teardrop-shaped cover or label 32 provides a sterility barrier for the contents of the outer shield 29. The label 32 attaches to a top flange 30 of the outer shield 29 and has a tab 34 serving as a handle (shown in FIG. 5). An inner shield or needle cover 28 covers the patient needle 11 within the outer shield 29. The inner shield 28 can be secured to the hub 20 to cover the patient needle 11 by any suitable means, such as an interference fit or a snap fit. The outer shield 29 and inner shield 28 are removed prior to use. The cap 21 fits snugly against outer sleeve 13 to allow a user to securely carry the pen injection device 50.
Individually packaged pen needle assemblies are often sold packed loosely in a container, such as a box. Boxes of various sizes are used for various quantities of the individually packaged pen needle assemblies (for example, a 50-count box or a 100-count box).